A
summary of decades of research on a rather 'out-there' idea involving viruses
from space has recently been published, and it's raising questions on just how
scientific we can be when it comes to speculating on the history of life on
Earth. This may sound weird and strange but it’s serious.
It's
easy to throw around words like crackpot, rogue, and maverick in describing the
scientific fringe, but every now and then a paper like this comes along,
leaving us blinking owlishly, unsure of where to even begin. A total of 33
names are listed as authors on this review, which was published by Progress in
Biophysics and Molecular Biology. The journal is peer reviewed and fairly well
cited. So it's not exactly small, or a niche pay-for-publish source.
Science
writer Stephen Fleischfresser goes into depth on the background of two of the
better known scientists involved: Edward Steele and Chandra Wickramasinghe.
It's well worth a read. For a tl;dr version, Steele is an immunologist who
already has a fringe reputation for his views on evolution that relies on
acquiring gene changes determined by the influence of the environment rather
than random mutations, in what he calls meta-Lamarckism.
Wickramasinghe,
on the other hand, has had a somewhat less controversial career, recognised for
empirically confirming Sir Fred Hoyle's hypothesis describing the production of
complex carbon molecules on interstellar dust. Wickramasinghe and Hoyle also
happened to be responsible for another space biology thesis. Only this one is
based on more than just the origins of organic chemistry. The Hoyle
Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology makes the rather simple
claim that the direction of evolution has been significantly affected by
biochemistry that didn't start on our planet.
In
Wickramasinghe's own words, “Comets are the carriers and distributors of life
in the cosmos and life on Earth arose and developed as a result of cometary
inputs.” Those inputs, Wickramasinghe argues, aren't limited to a generous
sprinkling of space-baked amino acids, either.
Rather,
they include viruses that insert themselves into organisms, pushing their
evolution into whole new directions. The report, titled "Cause of Cambrian
Explosion – Terrestrial or Cosmic?", pulls on existing research to
conclude that a rain of extra-terrestrial retroviruses played a key role in the
diversification of life in our oceans roughly half a billion years ago.
“Thus retroviruses and other viruses hypothesised to be liberated in cometary debris trails both can potentially add new DNA sequences to terrestrial genomes and drive further mutagenic change within somatic and germline genomes,” the authors write.
Let that
sink in for a moment. And take a deep breath before continuing, because that
was the tame part. It was during this period that a group of molluscs known as
cephalopods first stretched out their tentacles from beneath their shells,
branching into a stunning array of sizes and shapes in what seemed like a
remarkably short time frame.
The
genetics of these organisms, which today include octopuses, squid, and
cuttlefish, are as weird as the animals themselves, due in part to their
ability to their ability to edit their DNA on the fly. The authors of the paper
make the rather audacious claim that these genetic oddities might be a sign of
life from space. Not of space viruses this time, but the arrival of whole genomes
frozen in stasis before thawing out in our tepid waters.
“Thus the possibility that cryopreserved squid and/or octopus eggs, arrived in icy bolides several hundred million years ago should not be discounted,” they write.
In his review of the paper, medical researcher Keith Baverstock from the
University of Eastern Finland, concedes that there's a lot of evidence that
plausibly aligns with the H-W thesis, such as the curious timeline of the
appearance of viruses.
But that's just not how science advances. “I believe this paper justifies scepticism of the scientific value of stand alone theories of the origin of life,” Baverstock argues. “The weight of plausible, but non-definitive, evidence, great though that might be, is not the point.”
While
the idea is as novel and exciting as it is provocative, nothing in the summary
helps us better understand the history of life on Earth any better than
existing conjectures, adding little of value to our model of evolution. Still,
with solid caveats in place, maybe science can cope with a generous dose of
crazy every now and then. Journal editor Denis Noble concedes that 'further
research is needed', which is a bit of an understatement. But given the
developments regarding space-based organic chemistry in recent years, there's
room for discussion.
“As space chemistry and biology grows in importance it is appropriate for a journal devoted to the interface between physics and biology to encourage the debates,” says Noble. “In the future, the ideas will surely become testable.”
Just in
case those tests confirm speculations, we recommend being well prepared for the
return of our cephalopod overlords. Who knows when they'll want those eggs
back? This research was published in Progress in
Biophysics and Molecular Biology.